CIFS: SMBD: Read correct returned data length for RDMA write (SMB read) I/O
This patch is for preparing upper layer doing SMB read via RDMA write.
When RDMA write is used for SMB read, the returned data length is in
DataRemaining in the response packet. Reading it properly by adding a
parameter to specifiy where the returned data length is.
Add the defition for memory registration to wdata and return the correct
length based on if RDMA write is used.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 66d1ebf..49cf999 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -1455,6 +1455,7 @@ cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid)
struct cifs_readdata *rdata = mid->callback_data;
char *buf = server->smallbuf;
unsigned int buflen = get_rfc1002_length(buf) + 4;
+ bool use_rdma_mr = false;
cifs_dbg(FYI, "%s: mid=%llu offset=%llu bytes=%u\n",
__func__, mid->mid, rdata->offset, rdata->bytes);
@@ -1543,8 +1544,11 @@ cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid)
rdata->iov[0].iov_base, server->total_read);
/* how much data is in the response? */
- data_len = server->ops->read_data_length(buf);
- if (data_offset + data_len > buflen) {
+#ifdef CONFIG_CIFS_SMB_DIRECT
+ use_rdma_mr = rdata->mr;
+#endif
+ data_len = server->ops->read_data_length(buf, use_rdma_mr);
+ if (!use_rdma_mr && (data_offset + data_len > buflen)) {
/* data_len is corrupt -- discard frame */
rdata->result = -EIO;
return cifs_readv_discard(server, mid);